Targeting

An application based on version 2.0 of the Pen API can create multiple windows
and writing areas on the screen that simultaneously accept pen input.
Targeting allows the application to govern the distribution of input data to the proper
window.

For example, a forms application can establish targeting information for each
of several controls on the screen. Even if the user writes in the controls in
arbitrary order, targeting ensures the pen data arrives at the proper window
procedure.

For more information on targeting, see "Step 2: PE_SETTARGETS Message" in
Chapter 2, "Starting Out with System Defaults." Also see the reference sections for TARGET and TARGINFO in Chapter 11, "Pen Application Programming Interface Structures."